So you’ve got a bunch of plants growing in your tank and you don’t want them, huh? Weellllll crap, let’s deal with it.

“I’ve got Algae. What DooOoOooO?!”

Algae needs 2 things to grow; Namely nutrients and light. Remove either, and algae will not be able to grow.

Many people want to take a high-tech, expensive, instant approach to solving their algae problems, but the reality of the situation is that most of the time, those will treat the symptom and not the actual source of the problem.

Let’s walk through some of the most common algae issues, but first, let’s deal with this doozy.

“But my test kit shows my water is clean!”

Yeah man, that’s because the algae is eating everything from your water. It IS super clean. Clean enough to feed a garden of plants you don’t want.

Hair Algae

Mmmm.. yum yum, lots of green growing crud everywhere. Hair algae is super common and if left unchecked, it will grow in about any tank. It is very common in new tanks (tanks under 2-3 months old) and if the tank is cared for properly, it will likely go away on its own. If your tank is established and you’re getting hair algae, it’s likely due to too many nutrients or too much light.

Where do the nutrients come from? That is a good question. One only YOU can answer. The most common sources are:

  • Overfeeding
    • Most fish die fat and overweight. Fish eat less than you think. Yes they WILL eat a ton if you give them a ton. So will human children, or dogs, or about any creature. That doesn’t mean they should be fed until they’re bursting. MONITOR your fish, pay attention to their size and shape. If they are not concave, they are probably healthy. If they are, feed a little more. I have seen very successful tanks, with healthy fish that live for many years, that small amounts, every other day (monitoring their fish closely).
  • Crappy water
    • What do you use for your salt water? It is relatively safe to assume your local fish store (LFS) uses clean RODI water to make their salt water, but it’s not a bad idea to test anyways. If you are using tap water, though it might not be poisonous to your fish, it likely has a ton of disolved solids and other crud that will feed your tank. If your LFS sucks and doesn’t have good water, I recommend buying a good RODI system.
  • Over lighting
    • The bright lights of your tank should only be on for 4-6 hours a day MAX. If you want to see your tank, make sure you tune those lights so they’re on when you’re home and wanting to look at it. You can run your dim blues for longer, but your brights need to be limited.
  • Poor maintenance
    • How often do you perform water changes? If it’s on a small tank (almost regardless of how it’s stocked), you should really do at least weekly 10% water changes. Most folks run some sort of nano tank (30g or below), and the easiest thing to do in my opinion is just a 5gal water change. You have 5gal buckets, keep it simple.
    • How well do you clean your tank?
      • Rocks – Blow off your rocks with a turkey baster before you do your water change. Get all that crud off the front, back, and sides of the rock.
      • Sand Bed – Clean your sand bed with a sand bed cleaning tool.
      • All chambers of your tank – All the chambers of your tank, your sump, your fuge, your skimmer, all of that needs to be cleaned weekly as well. Detritus can hide anywhere. Make sure you’re cleaning that stuff out when you do your water changes.
      • Filter media – sponges, socks, pads, filter bags, everything. Clean it out!
  • Poor Flow
    • Do you have enough flow to keep undissolved solids suspended in the water until it can make it back to your filtration? Is your flow random? You would be amazed at what setting up timers and turning your powerheads off and on throughout the day will kick up. If you have fancy pumps with controllers, adjust the schedule so it changes throughout the day. Get that stuff up into the water so it can get filtered out.
  • Overstocked Tank
    • There is a limit to what you can put in your tank. If you overstock it, even if you feed appropriately, you’re going to generate more neutrients than your tank is capable of dealing with. Stock your tank responsibly.

If your algae problem is minor, there are some natural helpers that can assist. Your “Clean up Crew” (CuC), when arranged correctly, can help. It should be divided up into 3 areas.

  • Glass
    • A turbo snail does great work on keeping algae off of your smooth surfaces. They will clean your rock too, but prefer the glass and other flat surfaces.
  • Rocks
    • Hermit crabs will pick away at the rocks all day. They’re super cool and fun to watch with their mission impossible moves hanging upside down from your rock.
  • Sand Bed
    • Nassarius snails will crawl around under your sand bed and keep it moving around. When you feed the tank, they’ll pop up and lose their minds. Super fun to watch.
    • Another option is a sand sifting goby. They can grow quite large, however, so might not be a great option for a small tank.

Be careful choosing a CUC if you have fish like triggers, as they will happily eat snails and hermits.